fix(mysql): Add definition for PoolCluster.end with callback

types/mysql/index.d.ts

@@ -101,6 +101,7 @@ interface IPoolCluster {
     add(group: string, config: IPoolConfig): void;
 
     end(): void;
+    end(callback: (err: IError, ...args: any[]) => void): void;
 
     getConnection(callback: (err: IError, connection: IConnection) => void): void;
     getConnection(group: string, callback: (err: IError, connection: IConnection) => void): void;

types/mysql/mysql-tests.ts

@@ -17,7 +17,7 @@ connection.query('SELECT 1 + 1 AS solution', function (err, rows, fields) {
     console.log('The solution is: ', rows[0].solution);
 });
 
-connection.end();
+connection.end(function (err) {});
 
 connection = mysql.createConnection({
     host: 'example.org',
@@ -396,4 +396,4 @@ connection = mysql.createConnection({ debug: ['ComQueryPacket', 'RowDataPacket']
 
 var type: mysql.FieldType = mysql.FieldType.SHORT;
 var info: mysql.IFieldInfo;
-info.type = type;
+info.type = type;